Method for repair of rails

ABSTRACT

PROCESS AND APPARATUS FOR REPAIRING DEFECTS IN RAIL HEADS AND WEBS BY REMOVAL OF A PORTION OF THE RAIL HEAD EMBODYING THE DEFECTS, ENCLOSING THE REMOVED PORTION WITHIN A HOUSING HAVING A POURING SPACE SURROUNDING THE REMOVED PORTION AND A POURING BASIN COMMUNICATING WITH THE SPACE AND THROUGH WHICH THE MOLTEN METAL IS INTRODUCED AND A MEANS FOR PREHEATING THE RAIL PER PRIOR TO METAL POURING.

I 3 ID Nov. 30, 1971 2050 ETAL METHOD FOR REPAIR OF RAILS Filed Sept. 8, 1968 5 5 R z -y 0 d f T 1 Nwm 4 E03 zx W F, w ww [m1 mfl 27/71 V/ A// M L m/ 51 1 w Tu W m 6 i, F na United States Patent 3,623,207 METHOD FOR REPAIR OF RAILS Ivo Zoso, 316 Barry Ave., Chicago, Ill. 60657, and

Thomas F. Kennedy, Jr., 705 Benwood Drive, Carbondale, Ill. 62901 Filed Sept. 3, 1968, Ser. No. 756,978 Int. Cl. B22d 19/10; B23p 7/00 US. Cl. 29401 4 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a process and equipment for repairing defects in rail heads and web, such as transverse defects, wheel burns, horizontal split heads, spike maul nicks, detail fractures, compound fractures, and other head and web defects.

The fissures which begin inside the head of the rail are called transverse defects. They constitute a dangerous fault which is becoming more and more frequent due to the increase of the speed of trains, of their heavier loads and of the increased length of the rails, etc. Each of these transverse defects is the beginning of a complete rupture of the rail, and these transverse defects must be removed as soon as they are detected, as by detection devices or visual inspection.

In the case of a short rail (39 feet), the faulty rail is replaced, while in the case of a long rail (1440 feet) the defective part of the rail has to be replaced by a short piece of rail (20 feet long). In either event, such operations are very costly.

The best procedure for repairing the damage in the rail is to eliminate these transverse defects by cutting out a piece of rail each side of and including the part containing the transverse defect, then filling this space with thermit Welds, electric welds, or oxy acetylene.

Such a process, the application of which, at first, seems very easy, is not feasible under heavy trafiic if the joint is over one inch wide and if the transverse defect is not almost perpendicular to the axis of the rail so that the defect of the rail will be exactly located between the two cutting areas and be eliminated without any doubt.

On the other hand, the length of time that those operations require (cutting of the rail, verification that the transverse eflect is completely cut out, alignment of the rails, welding, etc.) is relatively long and cannot be done under heavy traffic.

It is an object of this invention to prevent all the inconvenience mentioned here above and one of its aims is a process for the repair of the heads of the rail which have become faulty after appearance of transverse defects or wheel burns, or any other defect as mentioned above, and it is a related object to provide the equipment for the practice of such a process.

These and other objects and advantages of this invention will hereinafter appear and for purposes of illustration, but not of limitation, an embodiment of the invention is shown in the accompanying drawing in which-- ice FIG. 1 is an elevational view of a part of the rail head having a transverse defect;

FIG. 2 is an elevational view taken crosswise of the rail, showing in partial cross-section the removable apparatus with an auxiliary head rail;

FIG. 3 is a transverse sectional view of the mold in position of use on the rail, covering areas ab-c-d of FIG. 1 cut out from the rail head;

FIG. 4 is a plan view showing the bottom of the pouring basin of the mold of FIG. 3;

FIG. 5 is an elevational view partially in section of the repaired piece of rail illustrating the concave bending which might occur upon cooling in the absence of the necessary precautions;

FIG. 6 is a plan view similar to that of FIG. 5 without the defect; and

FIG. 7 is an elevational view partially in section of the rail of FIG. 1 after cutting and removal of the defective part of the rail, showing the rail raised to a convex curvature to overcome the defect upon cooling.

The process according to this invention is noteworthy in that it consists in cutting and removing only a very large part of the head of the rail where the transverse defect has been detected, then to till the space, or cutting, left by the part of the head which has been removed, with a thermit weld, after having taken into consideration any bending of the rail caused by the cooling of the added weld and the surrounding area of the rail.

The measures to eliminate the concave bending of the rail, following its cooling, consist in raising, eventually after removal of the defective part of the head of the rail, but in any case before welding, the part of the rail where removal of the part of the head of the rail will take place, so that the rail is counter-bent on a convex curvature predetermined in such a manner that it will disappear after cooling of the thermit charges.

The equipment to apply the process mentioned here above consists essentially, whatever the means of cutting the head of the rail (cutting torch for instance), in an aluminothermit welding mold made of two symmetrical parts which can be joined one to the other so as to demarcate, on one hand, a space which will constitute a pouring room, which surrounds the space left by the part of the head of the rail which has been removed, space to be filled by the melting metal, which base communicates with some outlets opening at the top of the mold; on the other hand, a pouring basin located above the pouring room mentioned above, through a preheating passage which can be closed by a refractory plug. The welding mold is noteworthy by the fact that the plug of the preheating passage has twopouring channels spaced one from the other in the longitudinal direction of the axis of the rail. In a different manner, the bottom of the pouring basin still communicates with the pouring room through two other channels set laterally on each side of the joint plane of the two parts of the mold.

The material mentioned here above also includes, though not essential, a removable apparatus with an auxiliary rail head which can insure the passage of trains if necessary, between the time of cutting off of the part of the defective rail head and the time when the mold is set and the weld is set, this apparatus being remarkable in that it includes two angle bars, one of which is part of an inset piece which will fit the shape of the rail cutting, that is to say of the part of the head of the rail which has been removed, and which is made soas to rest on the other angle bar. The two angle bars can be joined against the other two sides of the rail with the inset piece being placed in the cut of the rail with clamps.

Other particulars and characteristics of the invention are made obvious by the following description which deals with practice of the above mentioned process, and the manner of use of the equipment.

The head 1 of the rail R shows a transverse defect T represented by a dotted line.

According to the process object of this invention, one cuts, in the rail, the part of the defective head of the rail, this cutting being done in the shape of a castle a-b-c-d, with a cutting torch. The width l of the castle will be given a standard value largely sufiicient so that We are certain that the transverseor otherdefect" (detected in a known manner with the help of track testing apparatus) is effectively contained in the piece of rail head taken out.

The standardization of the width 1 allows to insure temporarily, before the completion of the repair of the rail, the passage of one or more trains with the help of the apparatus shown on FIG. 2 and including two angle bars 2 and 3, one of which: angle bar 2 for instance, is part of a piece sensibly in the shape of the part of the head of the rail which has been cut out. The piece thus constitutes an auxiliary head of the rail, filling the space a-bcd and resting on bar 3. The two angle bars, after setting, are joined to the rail with two temporary clamps 5 of a known type.

By reason of the removable apparatus with auxiliary head rail described here above, it is possible to have enough time to proceed with a complete examination of surfaces a-b, b-c and c-d, and to allow one, or several trains if necessary, to go by, before proceeding with the welding.

Should there be no traffic, it is not necessary to use the auxiliary head rail apparatus described above.

After examination and cleaning of the surfaces mentioned above, a mold is installed over cut away part of rail a-b-c-d. The thermit welding mold M shown in FIG. 3 and composed of two symmetrical halves Ma and Mb are joined one against the other around the part of the rail containing the area to be repaired. These halfmolds define a pouring room 6 surrounding the castle cut abcd and a pouring basin 7 which communicates with the room through a passage 8 entering perpendicularly in the castle cut.

Passage 8 permits preheating of the part of the rail to be repaired and can be closed by a refractory plug 9 presenting, at its ends located on a parallel line to the longitudinal axis of the rail, two pouring passages 10a and 10b.

In a different manner, it is possible to provide two additional pouring passages 11a and 11b through which the bottom of basin 7 will communicate with room 6 and set on each side of the plan of symmetry of mold M.

The bottom of the pouring room 6* communicates, through passages 12, with the outlets 13 which open at the top of the mold.

The aluminothermic welding to replace with healthy metal the defective part of the head of the rail can be done without preheating of the area to be welded. It is preferred to preheat. This is done through passage 8 (after removing plug 9). Any hot gases will evacuate themselves through outlets 13 as well as through outlets 11a, 11b. Immediately after the preheating cycle is over (this does not generally last more than seven or eight minutes), plug 9 is set in place and the molten metal, obtained through aluminothermic reaction, is poured over it. The metal, running in basin 7, penetrates into the pouring room 6 through passages 10a and 10b, as well as through passages 11a and 1112, should the latter passages exist.

The first metal poured which has cooled itself on the rail, runs into outlets 13, through passages 12. When the bottom of outlets 13 is full of metal, the top of the room 6 fills u The washing action of the hot metal, or the surfaces of cutting to be welded, continues to take place during the whole pouring, since part of the metal runs through the passages 12 until the outlets 13 are completely filled and the balance of the liquid metal is established in the whole mold.

The process and apparatus presents several advantages (particularly in comparison with the replacing of short rails or pieces of long rails in which transverse-or any other-defects have been detected or in comparison with the filling, through welding, of the void left between two rail ends after removal of a piece of defective rail). It is unnecessary to realign the rails. In cold weather and for the repair of long rails, the rail can be preheated on each side of the area to be repaired so as to avoid too high a constraint of traction on the part of the rail dealt with.

In the absence of certain precautionary measures to be taken while preparing to use the new process of this invention, one takes the risk, at the time of the cooling of the rail, of a concave bending due to the contraction of the poured metal A. This (FIG. 5) contraction must not be opposed, otherwise it would result in the maintenance of dangerous tensions in the head of the rail.

In accordance with this invention, this drawback is prevented by raising the rail, before proceeding with the aluminothermic welding, so that the rail will present a convexity creating a high point which can be predetermined and measured (FIG. 7). The effort of the raising of the rail is stopped a few minutes after the pouring, that is to say when the added metal (through welding) has become solid enough to oppose all effect of compression. The realignment of the rail takes place automatically and exclusively under the contraction of the poured metal.

In a different manner, the realignment of the rail, after welding, can also be obtained by compensating the contraction of the poured metal by hydraulic press forging or by powerful hammering of the poured metal. These operations are facilitated by welding in such a manner that the poured metal in the head of the rail presents, on each side, an overthickness S of three to four millimeters (see FIG. 6).

If the welding has been preceded by preheating, the detected defect in the rail is such that it will necessitate ony a castle cut of small depth. The rail will deform itself during the preheating and will bend upward to reach the high point which will allow the rail in question to realign itself during the cooling. The only precaution to be taken is to allow the free deformation of the rail. This condition may necessitate, in cold weather, the preheating of the rail to a temperature close to average, on a length of around ten meters on each side of the defective area.

It will be understood that changes may be made in the details of construction, arrangement and operation without departing from the spirit of the invention, especially as defined in the following claims.

We claim:

1. A process for repair of defects in rail heads and webs comprising cutting and removing the head, and web of the rail in the area which includes the defect, filling the void left by the part of the head and rail which was removed with molten metal, and compensating for the contraction of the molten metal upon cooling.

2. The process as claimed in claim 1 in which the contraction of the molten metal upon cooling is compensated by raising part of the rail on which the replacement of the head of the rail will take place to provide a convex counterbend calculated to disappear upon cooling of the metal.

3. The process as claimed in claim 1 in which the contraction of the molten metal upon cooling is compensated by pouring the metal in an amount to provide an overthickness and by forging the metal after cooling with a hydraulic press.

4. The process as claimed in claim 1 in which the contraction of the molten metal upon cooling is compensated by a powerful hammering of the metal with the metal being poured to provide an overthickness upon cooling.

References Cited UNITED STATES PATENTS Falk 29--401 Deppeler 164-54 X Deppeler 164108 X Begtrup 1645 4 JOHNF. CAMPBELL, Primary Examiner 5 V. A. DIPALMA, Assistant Examiner U.S. C.l. X.R. 104--15 

